Secured sister-hook assembly



H. G. ALoFs 3,222,743

SECURED SISTER-HOOK ASSEMBLY Dec. 14, 1965 Filed Sept. 30, 1963 INVENTOR. HERMA/V G. A OFS BY MM EEE.

United States Patent 3,222,743 SECURED SlSER-HOOK ASSEMBLY Herman G. Alofs, 1512 Yorkshire SE., Grand Rapids, Mich. Filed Sept. 30, 1963, Ser. No. 312,581 Claims. (Cl. 24-165) This invention relates to the construction of coupling devices, and has been developed primarily to connect an automobile safety-belt to a floor terminal. The invention utilizes a type of connector commonly referred to as a sister-hook, which involves a pair of plates having hook formations such that the plates can be placed back-to-back, with the hooks partially superimposed to define an opening. Each of the hooks then has a p0rtion covering the opening of the other hook.

The opposite end of the plates (from the hooks) is normally adapted to receive a loop of belting. 'Ihe hooks can be separated to admit a terminal member, and subsequent ybelt tension Will be effectively transferred to the terminal. The problem with this type of device arises on the advent of subsequent slack conditions in the belt. Vibrations and random belt positions can easily permit the hook plates to separate enough to disengage from the terminal. The security of the safetybelt is then lost. The present invention has been developed as a means for preventing accidental separation of the plates, without impairing the utility and intended disengageability of the coupling.

The preferred form of the invention incorporates a spring device in the form Iof an axially-projected C- shaped cross-section of the type frequently encountered in large pivoted paper clips. The plates are received in the opening of the C, and the separation of the hooks (to admit a terminal fitting) is resisted by the resilience of the spring. The several features of thev invention will be analyzed in detail through a discussion of the particular embodiments illustrated in the accompanying drawing, in which:

FIGURE 1 is a perspective view of a fully assembled and locked device incorporating the present invention.

FIGURE 2 is a sectional elevation on the plane 2-2 of FIGURE 1, on a somewhat enlarged scale.

FIGURE 3 is a perspective View of a modified 'form of the invention.

FIGURE 4 is a sectional elevation on a plane 4-4 of FIGURE 3.

Referring to FIGURES 1 and 2, the plates generally indicated at and 11 are provided with the hook portions 12 and 13, respectively, which are superimposed so that the hook portions together define an opening 14.

The plate 10 is provided with the slots 15, 16, and 17, and the plate 11 with the slot 18. The belt 19 is interengaged with these slots in the manner best shown in FIGURE 2, which illustrates the -belt in slack condition. Application of tension to the portion of the belt will result in constricting the belt around the portions of the plates 10 and 11 between the slots 15-18.

The plates are biased to the closed conditions shown in FIGURES 1 and 2 by the action of the spring 21. This spring is received in the slots 15 and 1S of the plates, .and bears upon the plates at a point displaced from the edge of the slot. The plates 10 and 11 are provided with the offsets 22 and 23, respectively, to provide a tendency to maintain the spring 21 in the illustrated position to avoid interference with the belt as it passes through the slots 15 and 18. It will be obvious that the separation of the hooks 12 and 13 in a direction normal to the surface of the plates will induce an opening of the C-shaped cross-section of the spring 21, resulting in a resilient deformation of the spring "ice and the application of a biasing action tending to return the plates to the closed position. The formation of the spring 21 is such that some degree of biasing is applied to the plates even in the closed position.

In the event that it becomes desirable to further lock the plates together, or to lock them Without the use of a spring 21, holes along the axis of symmetry of the plates 10 and 11 are provided for receiving a cotter pin 24. At least the right-hand end of the plates 10 and 11 may then be formed on the same die, so that the inversion of the plates to establish the back-to-back relationship shown in FIGURES 1 and 2 will result in the alignment of the holes for receiving the cotter pin 24.

The modification shown in FIGURES 3 and 4 involves the use of identical plates 25 and 26. These plates are provided with the hooks 27 and 28, and with the slots 29 and 30 for receiving the loop 31 of the belt 32. The plates are also provided with the offsets 33 and 34 for positioning the spring 35, and it Will be noted that the plates also have the holes 36 and 37 on the axis of symmetry. These holes may be utilized for receiving a cotter pin as previously described.

The offsets 22-23 and 3334 may take a variety of forms, such as the preferred continuous ridge shown in the drawings, or these may be one or more isolated dimples or lanced portions of the material of the plates. Practically any form of projection will serve to position the spring 33 in the manner illustrated so that interference with the belting is avoided. The amount of discontinuity, or gap, in the springs 21 and 35 will be determined by the proportions of the device being constructed, and will also be a function of the thickness of material of the spring and of the amount of deflection that is desirable.

The particular embodiments of the present invention which have been illustrated and discussed herein are for illustrative purposes only, and are not to be considered as a limitation upon the scope lof the appended claims. In these claims, it is my intent to claim the entire invention disclosed herein, except as I am limited by the prior art.

I claim:

1. A sister hook assembly, comprising:

two similarly formed plates each having a hook portion and at least one slot for receiving belt means, said plates being normally positioned in opposite relationship whereby said hook portions overlap and dene together an opening,

said plates having a ridge adjacent said slot along the side thereof toward said hook portion, and

a C-shaped spring extending through said slots and having a gap, said spring receiving said plates in clamping relationship at said gap whereby separation of said hook portions causes resilient expansion of said spring and increase of said gap,

said spring bearing on said plates on the opposite side of said ridge from said opening to maintain said spring close to the adjacent edge of said plate at `said opening to avoid interference with said belt means. 2. A sister hook asse-mbly, comprising; two plates'each having a hook portion and at least one slot for receiving belt means, said plates being normally positioned in opposite relationship whereby said hook portions overlap and define together an opening,

at least one of said plates having a lateral projection adjacent said slot; and a C-shaped spring extending through said slots and having a gap, said spring receiving said plates in clamping relationship at said gap whereby separation of said hook portions causes resilient expansion 5. A safety belt and sister hook assembly, comprising: of said spring and increase of said gap, safety belt means; two plates each having a hook porsaid spring bearing on said plates on the opposite side of said projection from said opening to maintain said spring close to the adjacent edge tion and at least one slot receiving said belt means, said plates being normally positioned in opposite relationship whereby said hook portions overlap and 5 of said plate at said opening to avoid interferdene together an opening; ence with said belt means. spring retained on and engaging said plates and 3. A safety belt and sister hook asesmbly, comprising: biasing the same together; and said plates including Safety belt 11162115; l[W0 plates each having a hook pormeans retaining said spring located in its biasing ention and at least one slot receiving Said belt means, gagement with said plates, whereby temporary sepasaid plates being normally positioned in Opposite ration of said hook portions causes resilient deforrelationship whereby said hook portions overlap and mation 0f Said Spring for attachment and detachment dene together an opening, of said hook portions.

said plates each having a hole, said holes being normally in alignment; References Cited by the Examiner a C-shaped spring extending through said slots and UNITED STATES PATENTS having a gap, said spring rece1v1ng said plates 1n clamping relationship at said gap whereby separation 222324 12/1879 Stflpleton 24-242 of said hook portions causes resilient expansion of 3845 12 6/1888 Dillon 24-165 said spring and increase of said gap; and '951'538 3/1910 Menarf 59-87 disengageable pin means normally engaging said holes. 1541'314 6/1925 Baldy/m' 4. A safety belt and sister hook assembly, comprising: 1'561337 11/1925 Madlgan 24-242 safety belt means; two plates each having a hook por- 2456374 12/1948 C'fmer 24-233 tion and at least one slot receiving said belt means, 2761190 9/1956 Rltter 24-234 said plates being normally positioned in opposite re- 3128520 4/1964 Carter 24-265 X lationship whereby said hook portions overlap and FOREIGN PATENTS define together an opening; 596,085 7/1959 Italy a C-shaped spring extending through said slots and having a gap, said spring receiving said platesin WILLIAM FELDMAN, Primary Emmi-nen clamping relationship at said gap whereby separation of said hook portions causes resilient expansion of BENARD A- GELAK, Exmmfsaid spring and increase of said gap. 

1. A SISTER HOOK ASSEMBLY, COMPRISING: TWO SIMILARLY FORMED PLATES EACH HAVING A HOOK PORTION AND AT LEAST ONE SLOT FOR RECEIVING BELT MEANS, SAID PLATES BEING NORMALLY POSITIONED IN OPPOSITE RELATIONSHIP WHEREBY SID HOOK PORTIONS OVERLAP AND DEFINED TOGETHER AN OPENING, SAID PLATES HAVING A RIDGE ADJACENT SAID SLOT ALONG THE SIDE THEREOF TOWARD SAID HOOK PORTION, AND A C-SHAPED SPRING EXTENDING THROUGH SAID SLOTS AND HAVING A GAP, SAID SPRING RECEIVING SAID PLATES IN CLAMPING RELATIONSHIP AT SAID GAP WHEREBY SEPARATION OF SAID HOOK PORTIONS CAUSES RESILIENT EXPANSION OF SAID SPRING AND INCREASE OF SAID GAP, SAID SPRING BEARING ON SAID PLATES ON THE OPPOSITE SIDE OF SAID RIDGE FROM SAID OPENING TO MAINTAIN SAID SPRING CLOSE TO THE ADJACENT EDGE OF SAID PLATE AT SAID OPENING TO AVOID INTERFERENCE WITH SAID BELT MEANS. 